At present, there is provided a service which is widely used for transmitting a called party's preliminarily prepared message to a calling party or recording a message from the calling party when the called party cannot answer an incoming call.
Further, Japanese Patent Laid-Open No. 09-84140 discloses the following method. A plurality of messages is preliminarily stored in a mobile phone. When a call is received, the called party's mobile phone detects and displays the calling source, and further displays the plurality of messages stored. The called party confirms the calling source and selects a message suitable for the calling source. Then, the mobile phone transmits the selected message to the calling source.